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Kesimpta

Generic name: ofatumumab
Dosage form: injection, for subcutaneous use
Drug classes: CD20 monoclonal antibodies, Selective immunosuppressants

Medically reviewed by Melisa Puckey, BPharm. Last updated on Oct 3, 2024.

What is Kesimpta?

Kesimpta (ofatumumab) is a FDA approved medicine used to slow the progression and risk of relapses for specific forms of relapsing multiple sclerosis (MS). It is a once a month injection given under the skin (subcutaneously) that you can self-administer in your own home.

Kesimpta is from the group of medicines called CD20 monoclonal antibodies that targets B-cell antigens. Sometimes they are called B-cell therapy or B-cell depletion therapy. Kesimpta works by binding to and decreasing B-cells. This medicine will not cure MS, but is used to slow its progression and reduce relapse rate.

How does Kesimpta work?

MS is a chronic, ongoing disease that causes damage to the brain, spinal cord and optic nerves. This causes nerve signals to be interrupted and results in symptoms of numbness, tingling, mood changes, memory problems, pain, fatigue, blindness and/or paralysis. It is thought that B-cells play a critical role in MS which causes the immune system to attack nerves. Kesimpta works by binding to and decreasing the B-cells, which may slow your immune system attacking your nerves. This may decrease inflammation and reduce MS symptoms, slow your disability progression and lower relapse rate.

What is Kesimpta used for?

Kesimpta is used in adults with specific types of relapsing forms of multiple sclerosis (MS) including:

Arzerra (ofatumumab) contains the same active ingredient to Kesimpta (ofatumumab) but they are NOT to be used interchangeably. They are used to treat different conditions and are given by a different route of administration.

Warnings

Kesimpta can cause serious side effects, including:

Tell your healthcare provider right away if you have any infections or get any symptoms, including painful and frequent urination, nasal congestion, runny nose, sore throat, fever, chills, cough, or body aches.

Tell your healthcare provider right away if you get worsening tiredness or yellowing of your skin or white part of your eyes during treatment.

Who should not take Kesimpta?

Do not use this medicine if you:

Before using Kesimpta

Before using this medicine, tell your healthcare provider about all of your medical conditions, including if you:

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

How should I use Kesimpta?

See the detailed Instructions for Use that comes with Kesimpta for information about how to prepare and inject a dose of this medicine and how to properly throw away (dispose of) used pens or prefilled syringes.

Vumerity, Avonex, Copaxone, Aubagio, Tecfidera, Gilenya, Tysabri

Kesimpta side effects

Kesimpta may cause serious side effects, including:

See Important information

The most common Kesimpta side effects include:

These are not all the possible side effects of Kesimpta. Call your doctor for medical advice about side effects.

You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Kesimpta?

Tell your doctor about all your other medicines, especially drugs that weaken the immune system such as

This list is not complete. Other drugs may affect Kesimpta, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Does Kesimpta interact with my other drugs?

Enter other medications to view a detailed interaction report.

How should I store Kesimpta?

Keep Kesimpta and all medicines out of the reach of children.

General information about the safe and effective use of Kesimpta.

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use this medicine for a condition for which it was not prescribed. Do not give it to other people, even if they have the same symptoms that you have. It may harm them.You can ask your pharmacist or healthcare provider for information that is written for health professionals.

What are the ingredients in Kesimpta?

Active ingredient: ofatumumab
Inactive ingredients: Sensoready pen and prefilled syringe: arginine, disodium edetate, polysorbate 80, sodium acetate trihydrate, sodium chloride, and Water for Injection. Hydrochloric acid may be added.

Popular FAQ

What are monoclonal antibodies?

Monoclonal antibodies (mAbs) are man-made proteins that mimic the natural antibodies produced by our immune systems. Monoclonal antibodies can be formulated into medicines to treat various types of illnesses, such as cancer, rheumatoid arthritis or psoriasis. Continue reading

Is Kesimpta better than Ocrevus?

In patients with relapsing forms of multiple sclerosis, Kesimpta (ofatumumab) is thought to be more effective than Ocrevus (ocrelizumab) in some ways, but no clinical trials have directly compared the two drugs

Ocrevus is the only one of the two drugs approved to treat primary progressive multiple sclerosis Continue reading

What are 8 key Kesimpta side effects to watch out for?

Common side effects of Kesimpta include upper respiratory tract infections, injection-related reactions, headache, injection-site reactions, urinary tract infection, and back pain. Severe allergic reactions and infections are also possible. Continue reading

How long can Kesimpta be out of the fridge?

Kesimpta (ofatumumab) can be kept at room temperature for up to 7 days, as long as the temperature doesn’t get higher than 30 degrees C (86 degrees F). Continue reading

How long does it take for Kesimpta to work?

Kesimpta (ofatumumab) starts to work to lower B cells within a week of starting treatment. In studies, Kesimpta reduced the risk of worsening MS at 3 months of treatment. Continue reading

Where and how is Kesimpta injected?

Kesimpta (ofatumumab) is injected under the skin (subcutaneously). It should be injected into the stomach area, thigh, or outer upper arm. Continue reading

How is Arzerra administered and how long to work?

Arzerra (ofatumumab) is administered by an intravenous infusion. It is diluted into a sterile bag of 1000mL sodium chloride for intravenous infusion which is then hung up and the infusion administered into one of your veins via an intravenous line. How long the infusion takes depends on your stage of Chronic Lymphocytic Leukemia (CLL) and if you have had treatment before, but initially Arzerra is usually administered over about 6 hours. The time of the infusion may be shortened, depending on how well you tolerate Arzerra. Continue reading

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.